This invention relates in general to manufacturing fiberglass articles, and in particular to a method for manufacturing corrugated fiberglass panels with co-impregnated gelcoat.
The most common type of fiberglass panels are constructed by using short fiberglass filaments and a resin, then molding the resin into the shape of a corrugated panel in a continuous process. A disadvantage of this type of panel is that it lacks strength. Also, the sun deteriorates the resin, exposing the filaments to the elements. The filaments will allow seepage of moisture, eventually causing the panel to crack and disintegrate.
It is known that continuous fiberglass filaments combined with a layer of woven fiberglass filaments will add strength to an article. See, for example, U.S. Pat. No. 4,029,172. It is also known that a layer of gelcoat on top of the fiberglass filaments and resin will improve the resistance to sun damage. Gelcoat is also a fiberglass resin but contains a filler material and a pigment such as titanium dioxide to shield the structural resin from the sun. In the prior art, gelcoat has been sprayed on a forming tool or mold surface, and allowed to partially harden before application of the structural laminate. This has been necessary to prevent migration of the gelcoat resin into the structural resin or migration of the fiber to the sun exposed surface of the part. This operation is generally related to manual procedures and, therefore, is labor intensive.
Methods for incorporating a gelcoat which is distinct and of finite thickness over the glass laminate have not been developed save for the above method. Current corrugated panel production processes simply add fillers and pigments to the structural resin systems. This does resolve the UV protection problem, but it does not eliminate the migration of the glass fiber to the surface.